Tiny metallic nanoparticles have the potential to change the landscape of defense technology, from obscuring warfighters from view to providing transparent displays in aircraft and vehicles. A nanoparticle is defined as a particle with one or more dimensions measuring 1 billionth of a meter (1 nanometer [nm]). Typical nanoparticles range from 1 to 1,000 nm. A typical human hair is about 90,000 nm thick. Therefore, an item of 1 nanometer would be invisible to the naked eye. Scientists at the...
Topics: DTIC Archive, DEFENSE ACQUISITION UNIV FT BELVOIR VA, *NANOPARTICLES, DISPLAY SYSTEMS, GOLD,...
The utilization of the plasmonic response of aptamer-gold nanoparticle conjugates (Apt-AuNPs) to design cross-reactive arrays for fingerprint identification of small molecular targets was demonstrated for the first time. Four aptamers with different structural features previously selected to bind different targets were used in combination with AuNPs by adsorbing the DNA on the AuNPs surface. The optimized response of the Apt-AuNPs to the analytes showed that, depending on the specific aptamer...
Topics: DTIC Archive, UES INC DAYTON OH, *DEOXYRIBONUCLEIC ACIDS, CLUSTERING, FINGERPRINT RECOGNITION,...
This project in its final form has focused on hydrogen production from ethanol and water-ethanol mixtures over a range of different gold-titania photocatalysts. Gold supported on a commercial anatase: rutile mixture has been found to be 3 times more active for hydrogen production than the previously reported gold on anatase photocatalysts. Other products detected were ethene and acetaldehyde; these products were enhanced in the presence of water. In-situ EPR spectroscopy was used to show that...
Topics: DTIC Archive, ABERDEEN UNIV (UNITED KINGDOM), *ETHANOLS, CATALYSIS, GOLD, HYDROGEN, PHOTOCHEMICAL...
The team led by PI Quan Li has conceptualized and rationally synthesized many novel functional hybrid gold nanorods (GNRs) and liquid crystal media. Now this project has accomplished all the proposed objectives and beyond. Organo-soluble chiral azo thiol monolayer-protected gold nanorods, the first of its kind, were synthesized and characterized. More importantly, the chirality of the hybrid GNRs was optically tunable. Moreover, organo-soluble porphyrin mixed monolayer-protected GNRs, porphyrin...
Topics: DTIC Archive, KENT STATE UNIV OH LIQUID CRYSTAL INST, *ENCAPSULATION, *GOLD, *NANOSTRUCTURES,...
Here we present the synthesis of the enzyme DNase 1 stabilized gold nanoclusters (DNase 1:AuNCs) with core size consisting of either 8 or 25 atoms. The DNase 1:Au8NCs exhibit blue fluorescence whereas the DNase 1:Au25NCs are red emitting. In addition to the intense fluorescence emission, the synthesized DNase 1:AuNC hybrid retains the native functionality of the protein, allowing simultaneous detection and digestion of DNA with a detection limit of 2 microg/mL. The DNase 1:AuNCs could be...
Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *FLUORESCENCE, *GOLD, *RIBONUCLEASE,...
In this study, diffusion of single adatoms and mono-vacancies on Au(100), Ag(110) and W(100) was investigated. The measurements on Au(100) and Ag(110) were conducted with using Scanning Tunneling Microscope (STM), whereas measurements on W(100) were conducted with using Field Ion Microscope (FIM). The activation energy for Au adatom diffusion on Au(100) surface was found to be 0.32+ or - 0.02eV and diffusion of mono-vacancies has been observed. The vacancies were created via Ne+ ion sputtering....
Topics: DTIC Archive, ILLINOIS UNIV AT URBANA-CHAMPAIGN, *GOLD, ACTIVATION ENERGY, ADATOMS, DIFFUSION,...
Protein encapsulated gold nanocluster (P-AuNC) synthesis was first demonstrated in 2009. Initially these P-AuNCs were used as cellular imaging agents as the protein shell surrounding the AuNC made them highly biocompatible. However, recent studies have begun to show that these stabilizing proteins may also retain native biological function thus giving a dual functionality to these hybrid molecules. Here we present the synthesis of DNase 1 stabilized gold nanoclusters (DNase 1:AuNCs) with core...
Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *FLUORESCENCE, DEOXYRIBONUCLEIC ACIDS,...
The purpose of the project is to develop plasmonic couplers and infrared detectors to realize multi-functional infrared sensors. The PI investigated in analyzing a novel detector structure for pixel-level multi-spectral infrared imaging; perforated gold films with Si3N4 overlayers, studied the fundamental understanding of surface plasmon polariton modes and their angle dependence; the effect of confinement barriers of InAs/InGaAs sub-monolayer (SML) quantum dots-in-a-well based infrared...
Topics: DTIC Archive, KOREA RESEARCH INST OF STANDARDS AND SCIENCE DAEJEON (SOUTH KOREA), *INFRARED...
Topics: DTIC Archive, AUCKLAND UNIV (NEW ZEALAND), *COATINGS, *COMPOSITE MATERIALS, ADDITIVES, CORROSION...
The overall goal of this research was to utilize rapid surface plasmon spectroscopy to develop a new platform to correlate catalytic performance and behavior with catalyst morphology (e.g., size, shape) of individual core/shell nanoparticles. Kinetic experiments were performed on dihydrogen adsorption, but the findings are expected to be generally relevant to other surface-critical heterogeneous chemistries. Comparative studies of Au/TiO2/Pt, Au/ZnO/Pt, Au/SiO2/Pt were done to evaluate the...
Topics: DTIC Archive, MELBOURNE UNIV PARKVILLE (AUSTRALIA), *CATALYSTS, *PLASMONS, *SPECTROSCOPY,...
Unlike silver and gold, aluminum has material properties that enable strong plasmon resonances spanning much of the visible region of the spectrum and into the ultraviolet. This extended response, combined with its natural abundance, low cost, and amenability to manufacturing processes, makes aluminum a highly promising material for commercial applications. Fabricating Al-based nanostructures whose optical properties correspond with theoretical predictions, however, can be a challenge. In this...
Topics: DTIC Archive, RICE UNIV HOUSTON TX, *ALUMINUM, *PLASMONS, GOLD, HYPERSPECTRAL IMAGERY, LOW COSTS,...
Nanoparticles are potential threats to human health and the environment; however, their medical applications as drug carriers targeting cancer cells bring hope to contemporary cancer therapy. As a model drug carrier, gold nanoparticles (GNPs) have been investigated extensively for in vivo toxicity. The effect of GNPs on the immune system, however, has rarely been examined. Antibody-secreting cells were treated with GNPs with diameters ranging from 2 to 50 nm. The GNPs enhanced IgG secretion in...
Topics: DTIC Archive, NATIONAL CHIAO TUNG UNIV HSINCHU (TAIWAN), *CELLS(BIOLOGY), *NANOPARTICLES,...
Two-photon absorption (TPA) is a phenomenon of great interest for various optical limiting applications. The enhancement of molecular TPA cross-sections by placement of TPA chromophores within the plasmonic field of resonant and nonresonant plasmonic gold nanoparticles was explored. Polyelectrolyte layer-by-layer wrapping was employed to provide spacer layers between the chromophores and the gold surface. For on-resonant cases, TPA cross-sections could be enhanced by a factor of 40 for...
Topics: DTIC Archive, ILLINOIS UNIV AT URBANA DEPT OF CHEMISTRY, *GOLD, *NANOPARTICLES, *OPTICAL MATERIALS,...
The ability to construct self-assembled three-dimensional (3D) superstructures with desired functionality is not only of scientific curiosity but also crucial in the bottom-up nanofabrication of smart materials and devices. Here a facile solution-processable strategy for creating 3D layer-by-layer graphene gold nanoparticle architectures was developed in which cysteine molecules with amino groups were chemically grafted onto the surface of graphene oxide and then the cysteine thiol groups were...
Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING...
The purpose of this research is to investigate the effects of surface roughness and aging environment on the electrical contact resistance and residual stress in nickel and nickel/gold coated copper. In order to accomplish these research objectives, oxygen free copper coupons were prepared to a variety of average surface roughnesses (Ra ranging from 0.05 urn to 2.5 urn) prior to coating application. Three coating systems were investigated: Au/Ni plating, Ni plating, and Ni sputtering. The...
Topics: DTIC Archive, PENNSYLVANIA STATE UNIV STATE COLLEGE APPLIED RESEARCH LAB, *AGING(MATERIALS),...
DNase 1-stabilized gold nanoclusters (DNase 1 AuNCs) were synthesized with multiple energy levels in a metal-concentration-dependant fashion. From multiple characterization techniques including fluorescence spectroscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy, we assigned 2 reaction products to contain pure populations of clusters with core sizes of 8 and 25 Au atoms for the products where 10- and 2.5-mM HAuCl4 was used in the reaction,...
Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *X RAY PHOTOELECTRON SPECTROSCOPY,...
